U.S. patent application number 13/217116 was filed with the patent office on 2012-06-28 for intra-operative blood recovery system.
Invention is credited to Robert KRENSKY, David G. MATSUURA, Philip J. SIMPSON.
Application Number | 20120165642 13/217116 |
Document ID | / |
Family ID | 46312937 |
Filed Date | 2012-06-28 |
United States Patent
Application |
20120165642 |
Kind Code |
A1 |
KRENSKY; Robert ; et
al. |
June 28, 2012 |
INTRA-OPERATIVE BLOOD RECOVERY SYSTEM
Abstract
A method for recovering blood from a blood-laden surgical sponge
for autologous reinfusion, the method comprising the steps of:
conveying negative pressure to a housing with the blood-laden
surgical sponge; applying a predetermined force to draw the blood
from the surgical sponge; and collecting the recovered blood.
Inventors: |
KRENSKY; Robert; (Toronto,
CA) ; MATSUURA; David G.; (Encinitas, CA) ;
SIMPSON; Philip J.; (Encinitas, CA) |
Family ID: |
46312937 |
Appl. No.: |
13/217116 |
Filed: |
August 24, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61426965 |
Dec 23, 2010 |
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61444501 |
Feb 18, 2011 |
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61448963 |
Mar 3, 2011 |
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Current U.S.
Class: |
600/371 ;
137/561R |
Current CPC
Class: |
A61M 1/0281 20130101;
A61M 1/0009 20130101; A61M 1/0001 20130101; Y10T 137/8593 20150401;
A61M 1/0056 20130101; A61M 1/3627 20130101 |
Class at
Publication: |
600/371 ;
137/561.R |
International
Class: |
A61B 5/02 20060101
A61B005/02; F03B 11/02 20060101 F03B011/02 |
Claims
1. An apparatus for recovering fluid from a fluid retaining
structure, said apparatus comprising: a vessel for receiving said
fluid retaining structure, said vessel comprising a port; and
wherein said port is coupled to a source of negative pressure, and
said negative pressure conveyed to said vessel applies a force on
said fluid retaining structure to cause egress of said fluid from
said fluid retaining structure.
2. The apparatus of claim 1 wherein said vessel comprises a
reservoir for receiving said fluid.
3. The apparatus of claim 2 wherein said vessel comprises a barrier
between said fluid retaining structure and said reservoir, and
wherein said barrier comprises at least one aperture in fluid
communication with said reservoir.
4. The apparatus of claim 2 further comprising a strainer received
by an opening of said vessel, said strainer having a body with a
plurality of apertures in a portion thereof, said strainer
receiving said fluid retaining structure, and wherein said
reservoir receives said fluid via said plurality of apertures.
5. The apparatus of claim 4 wherein said strainer is cylindrical
and comprises a small diameter lower section joined to a large
diameter upper section by a first flange, said small diameter lower
section having a base with said plurality of apertures and said
large diameter upper section having a mouth defined by a first
rim.
6. The apparatus of claim 5 wherein said strainer is received by
said vessel such that said first flange rests on said vessel.
7. The apparatus of claim 6 further comprising a piston introduced
into said strainer, said piston caused to travel within said
strainer by said negative pressure, wherein said piston acts on
said fluid retaining structure to cause egress of said fluid.
8. The apparatus of claim 7 wherein said piston comprises a shaft
separating an upper piston head for engaging said large diameter
upper section and a lower piston head for engaging said small
diameter lower section.
9. The apparatus of claim 8 wherein said negative pressure conveyed
to said vessel to said large diameter section is multiplied by a
factor of at least two to said small diameter lower section.
10. The apparatus of claim 9 wherein said upper piston head
comprises an edge having a recessed groove for receiving a seal
member therein.
11. The apparatus of claim 10 wherein said vessel comprises a
second base having a sidewall extending therefrom with a second rim
defining a chamber and a rim opening, said second rim having a
second flange extending therefrom and a ring wall extending from
said second flange.
12. The apparatus of claim 11 wherein a gasket rests on said second
flange, such that an air-tight cavity is defined between said upper
piston head and said reservoir when said first flange rests on said
gasket and said seal member slidably engages said large diameter
upper section.
13. The apparatus of claim 12 wherein said vessel comprises an
outlet in fluid communication with said chamber.
14. The apparatus of claim 13 wherein said outlet is coupled to an
external device to receive said recovered fluid, said outlet having
a valve to control the flow of said fluid.
15. A method for recovering fluid from a fluid retaining structure
and collecting said fluid in a vessel, the method comprising the
steps of: associating said vessel with a perforated barrier;
introducing said fluid retaining structure into said vessel to abut
said barrier in said vessel; providing a force to said fluid
retaining structure to cause egress of said fluid from said fluid
retaining structure; wherein said fluid passes through said
perforated barrier into a reservoir of said vessel.
16. The method of claim 15 comprising the further step of operating
a source of negative pressure to convey negative pressure to said
vessel to provide said force, wherein said conveyed negative
pressure is monitored.
17. The method of claim 16 wherein said barrier is a strainer
received by an opening of said vessel, said strainer having a body
with a plurality of apertures in a portion thereof.
18. The method of claim 17 wherein via said vessel comprises a port
coupled to said source of negative pressure.
19. The method of claim 15 comprising the further step of operating
a source of positive pressure to convey positive pressure to said
vessel to provide said force.
20. An apparatus for recovering blood from a sponge containing said
blood, said apparatus comprising: a receptacle defining an internal
chamber; a sponge retaining housing comprising a perforated base,
said sponge retaining housing being received by said receptacle; at
least one piston received by said sponge retaining housing, said at
least one piston caused to advance and force said sponge against
said perforated base; and wherein said blood is forced out of said
sponge and said blood flows through said perforated base into said
receptacle.
21. The apparatus of claim 20 wherein said receptacle comprises a
port coupled to a source of negative pressure, and wherein said
negative pressure causes said at least one piston to advance toward
said perforated base to exert a force on said sponge.
22. The apparatus of claim 21 wherein said sponge retaining housing
is sealingly coupled to said receptacle, and said at least one
piston sealingly engages said sponge retaining housing to create an
air-tight chamber.
23. The apparatus of claim 20 wherein said force is applied by at
least one of a negative pressure, a positive pressure, a mechanical
unit, and an electro-mechanical unit.
24. A method for monitoring blood loss, the method comprising the
steps of: absorbing blood from a site with a surgical sponge;
removing said surgical sponge from said surgical site; introducing
said sponge into a vessel, said vessel comprising at least one
port; coupling said at least one port to a source of negative
pressure outside said vessel; and operating a source of negative
pressure to convey negative pressure to said vessel in response to
said negative pressure forcing the egress of said fluid from said
sponge; collecting said recovered blood received via said at least
one aperture; and measuring the amount of recovered blood.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S.
Provisional Application Ser. No. 61/426,965, filed on Dec. 23,
2010; U.S. Provisional Application Ser. No. 61/444,501, filed on
Feb. 18, 2011; and U.S. Provisional Application Ser. No. 61/448,963
filed on Mar. 3, 2011.
FIELD OF THE INVENTION
[0002] The present invention relates to medical devices, and more
particularly to intra-operative blood recovery systems.
BACKGROUND OF THE INVENTION
[0003] Autologous blood transfusion or autotransfusion is the
collection and reinfusion of a patient's own blood products.
Autologous blood is preferred in some instances because the blood
type will always match, and if only autologous blood is used during
surgery then the risk of exposure to infectious diseases, such as,
hepatitis or HIV from blood, is substantially eliminated, and the
risk of allergic reactions, or other adverse reactions, is
significantly reduced.
[0004] Generally, during a surgical procedure autologous blood
transfusion may be facilitated by either a blood processing device,
such as a cell-saver type machine or a cardiopulmonary bypass (CPB)
machine. The CPB machine is directly connected to the patient by
tubing which allows for continuous recovery of blood from a body
cavity and reinfusion of the patient's blood. The "cell-saver"
method requires the recovered blood to be processed (spun, washed,
etc.) and then bagged for reinfusion via a typical intravenous
route.
[0005] Surgical sponges are also commonly used during surgical
procedures to absorb body fluids of the patient, such as blood,
both inside the incision or around the site of the surgery. Sponges
of this nature are usually made of an open-meshed absorbent fabric,
such as woven cotton. The sponge may be re-used or discarded and
the process repeated as many times as is necessary during the
surgical procedure. Typically, the blood is recovered from the
sponge by either physically wringing the sponge or by soaking the
sponge in a saline solution, and then the blood and saline solution
are suctioned either into the cell saver where the red blood cells
are washed, spun and returned to the patient, or directly by a CPB
machine. The wringing method has a number of drawbacks, such as,
loss of blood from splatter and residual blood remaining on hands.
In addition, this method is time-consuming, inefficient, and has
the potential to physically damage the blood cells due to the
compressional and torsional forces. Furthermore, the amount of
blood recovered from the sponges is variable, and depends on the
individual's strength, technique and stamina. In addition, the
wringing method is not particularly aesthetic and is generally
considered as being undesirable by most users.
[0006] It is an object of an aspect of the following to mitigate or
obviate at least one of the above-mentioned disadvantages.
SUMMARY OF THE INVENTION
[0007] In one aspect of the invention, there is provided an
apparatus for recovering fluid from a fluid retaining structure,
said apparatus comprising: [0008] a vessel for receiving said fluid
retaining structure, said vessel comprising a port; and [0009]
wherein said port is coupled to a source of negative pressure, and
said negative pressure is conveyed to said vessel to apply a force
on said fluid retaining structure to cause egress of said fluid
from said retaining structure.
[0010] In another of its aspects, there is provided a method for
recovering fluid from a fluid retaining structure and collecting
said fluid in a vessel, the method comprising the steps of: [0011]
associating said vessel with a perforated barrier; [0012]
introducing said fluid retaining structure to abut said barrier in
said vessel; [0013] providing a force within said vessel to cause
egress of said fluid from said fluid retaining structure; wherein
[0014] said fluid passes through said perforated barrier into a
reservoir of said vessel.
[0015] In another of its aspects, there is provided an apparatus
for recovering blood from a sponge containing said blood, said
apparatus comprising: [0016] a receptacle defining an internal
chamber; [0017] a sponge retaining housing comprising a perforated
base, said sponge retaining housing being received by said
receptacle; [0018] at least one piston received by said sponge
retaining housing, said at least one piston being caused to force
said sponge against said perforated base; and [0019] wherein said
blood is forced out of said sponge and said blood flows through
said perforated base into said receptacle.
[0020] In another of its aspects, there is provided a method for
monitoring blood loss, the method comprising the steps of: [0021]
absorbing blood from a surgical site with a surgical sponge; [0022]
removing said surgical sponge from said surgical site; [0023]
introducing said sponge into a vessel, said vessel comprising at
least one port; [0024] coupling said at least one port to a source
of negative pressure outside said vessel; and [0025] operating said
source of negative pressure to convey negative pressure to said
vessel in response to said negative pressure forcing the egress of
said fluid from said sponge; [0026] collecting said recovered blood
received via said at least one aperture; and [0027] measuring the
amount of recovered blood from said surgical sponge.
[0028] In another of its aspects, there is provided an apparatus
for recovering blood from a sponge containing said blood, said
apparatus comprising: [0029] a housing defining an internal cavity;
[0030] said housing having an opening to introduce said sponge
therein; [0031] a port to permit fluid flow from said internal
cavity; [0032] a barrier intermediate said sponge and said port,
said barrier having at least one aperture to allow fluid
therethrough; and [0033] wherein said blood is forced out of said
sponge by a force applied to said sponge.
[0034] In another of its aspects, there is provided a method for
recovering blood from a blood-laden surgical sponge for autologous
reinfusion, the method comprising the steps of: [0035] conveying
negative pressure to a housing with said surgical sponge; [0036]
applying a predetermined force to draw said blood from said
surgical sponge; and [0037] collecting said recovered blood.
[0038] In another of its aspects, there is provided an apparatus
for recovering blood from a sponge containing said blood, said
apparatus comprising: [0039] a receptacle defining an internal
chamber; [0040] a sponge retaining housing comprising a perforated
base, said sponge retaining housing being received by said
receptacle; [0041] a member received by said sponge retaining
housing, said member caused to urge said sponge against said
perforated base; and [0042] wherein said blood is forced out of
said sponge and said blood flows through said perforated base into
said receptacle.
[0043] Advantageously, the blood recovery apparatus is more
effective in recovering blood from the blood-laden surgical sponges
for autologous reinfusion than prior art methods. Furthermore, the
apparatus is more consistent, potentially more effective,
especially in long operating procedures, and potentially less
damaging to the blood cells. Also, the apparatus allows for
improved monitoring of blood loss from a patient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] Several exemplary embodiments of the present invention will
now be described, by way of example only, with reference to the
appended drawings in which:
[0045] FIG. 1 shows an exemplary apparatus for recovering
blood;
[0046] FIG. 2 shows the apparatus of FIG. 1 in its assembled
form;
[0047] FIG. 3 shows a cross-section of the apparatus of FIG. 2
along line B-B';
[0048] FIG. 4 shows another exemplary apparatus for recovering
blood, in another embodiment;
[0049] FIG. 5 shows another exemplary apparatus for recovering
blood, in yet another embodiment; and
[0050] FIGS. 6 to 12 show different views of another exemplary
apparatus for recovering blood, in yet another embodiment.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0051] The detailed description of exemplary embodiments of the
invention herein makes reference to the accompanying block diagrams
and schematic diagrams, which show the exemplary embodiment by way
of illustration and its best mode. While these exemplary
embodiments are described in sufficient detail to enable those
skilled in the art to practice the invention, it should be
understood that other embodiments may be realized and that logical
and mechanical changes may be made without departing from the
spirit and scope of the invention. Thus, the detailed description
herein is presented for purposes of illustration only and not of
limitation. For example, the steps recited in any of the method or
process descriptions may be executed in any order and are not
limited to the order presented.
[0052] Moreover, it should be appreciated that the particular
implementations shown and described herein are illustrative of the
invention and its best mode and are not intended to otherwise limit
the scope of the present invention in any way. Indeed, for the sake
of brevity, certain sub-components of the individual operating
components, conventional data networking, application development
and other functional aspects of the systems may not be described in
detail herein. Furthermore, the connecting lines shown in the
various figures contained herein are intended to represent
exemplary functional relationships and/or physical couplings
between the various elements. It should be noted that many
alternative or additional functional relationships or physical
connections may be present in a practical system. Like elements in
the various exemplary embodiments are represented by like reference
numerals.
[0053] FIG. 1 shows an illustration of an exemplary blood recovery
apparatus 10, comprising a receptacle 12 supporting a strainer
basket 14 for receiving a fluid retaining structure, such as a
surgical sponge, generally designated by reference numeral 16. The
apparatus 10 also comprises a flexible membrane or diaphragm 18
which covers the strainer basket 14 as a lid, to sealingly and
removably secure the strainer basket 14 to the receptacle 12. The
receptacle 12 also includes a port 20 coupled to a source of
negative pressure i.e. pressure that is below surrounding (ambient)
pressure, for facilitating the recovery of the fluid from the fluid
retaining structure 16. Typically, a fluid 21, such as blood, is
retained by the surgical sponge 16 which is constructed from an
absorbent material, e.g., a low-count open-mesh gauze or washed
gauze fabric sheet, such as woven cotton. The sheet may include a
plurality of folds defining a multiple ply configuration of the
sponge 16.
[0054] In more detail, the receptacle 12 is generally cylindrical
in nature, comprising a base 22, sidewall 24 extending from the
base 22 to define an interior chamber or cavity 25 having an
opening 26 with a flange 27 extending outwardly therefrom. A
reservoir 29 for the recovered fluid is formed in the chamber 25,
and the port 20 is located in the sidewall 24, and adjacent to the
opening 26. Generally, the strainer basket 14 is bowl-shaped and
includes a perforated body 28 with a plurality of apertures 30
therethrough, and a flange 32 extending from the strainer basket
opening 34. The apertures 30 extend through body 28 to allow for
fluid, such as recovered blood 21, to pass therethrough. The
receptacle flange 27 and the strainer basket flange 32 sealingly
but removably engage each other, such that the strainer basket 14
fits snugly on the receptacle 12. The diaphragm 18 is dimensioned
to cover the strainer basket opening 34, and comprises a generally
uniform thickness across its entire diametric dimension, and a
peripheral snap ring 36 defining the outer periphery. The
peripheral snap ring 36 is shaped to matingly engage the flanges 27
and 32, thus sealingly and removably securing the strainer basket
14 to the receptacle 12. Preferably, the diaphragm 18 is
semi-rigid, or is fabricated from a material having a density that
allows the diaphragm 18 to be moved in response to the negative
pressure within the interior chamber 25. Suitable materials for the
diaphragm 18 may include plastic, such as, thermoplastic urethane
(TPU) or thermoplastic elastomer (TPE), among others. The diaphragm
18 may also include a durable, rigid cover to shield the diaphragm
18 from damage due to sharp surgical instruments or other
objects.
[0055] The port 20 extends from the interior chamber 25 of the
receptacle 12 through the sidewall 24, with a spout 38 extending
from the other side of the sidewall 24. Accordingly, a passageway
40 is formed to provide fluid communication with the chamber 25.
The spout 38 may comprise a connector for coupling a hose to the
source of negative pressure which provides a suction force, such as
a suction device or vacuum terminal 42, such as that found in a
hospital or laboratory environment. The connector may include a
valve mechanism for permitting only air flow from the chamber 25,
while impeding the flow of blood therethrough.
[0056] In operation, the apparatus 10 is easily assembled by
placing the strainer basket 14 on the receptacle 12 such that the
strainer basket flange 32 is supported by the receptacle flange 27,
as shown in FIGS. 2 and 3. Blood-laden surgical sponges 16 are
removed from a surgical site or a site with blood loss, and
introduced into the strainer basket 14 via the opening 34, and come
to rest on the perforated body 28. Typically, a predetermined
number of blood-laden surgical sponges 16 are placed in the
strainer basket 14 such that the capacity of the reservoir 29 is
not exceeded, otherwise the efficiency of the vacuum terminal 42
may be compromised. The diaphragm 18 is placed over the strainer
basket 14 and the snap ring 36 forces the flanges 27 and 32
together to create an air-tight seal. As such, air may only escape
from the assembled apparatus 10 via the port 20. A suitable hose is
connected to the connector to convey the pressure by the vacuum
terminal 42.
[0057] Generally, as the vacuum terminal 42 draws air out of the
chamber 25, and from the strainer basket 14 via the apertures 30, a
partial vacuum is created within the assembled apparatus 10, and
the negative pressure causes the diaphragm 18 to collapse on the
blood-laden sponges 16, thus compressing the sponge 16, as shown in
FIG. 2. The diaphragm 18, however, remains sealingly engaged to the
receptacle 12 via the snap ring 36, thus maintaining the air-tight
seal. Accordingly, the combined forces imparted by the diaphragm 18
and the negative pressure forces the blood out of the blood-laden
sponges 16, which flows into the reservoir 29 via the apertures 30.
Since the negative pressure is dispersed over the entire area of
the perforated body 28, instead of being concentrated over a
smaller area, the potential hemolytic effects due to the negative
pressure are potentially minimized. Once a substantial amount of
blood has been forced out of the sponges 16, or after a
predetermined time, the vacuum terminal 42 may be stopped. For
instance, the predetermined time may be correlated to the known
time period required to recover the most blood for a predetermined
number of sponges 16. The volume of the recovered blood 21 in the
reservoir 29 may be measured via indicia on the receptacle 12, thus
providing an effective means for monitoring the blood loss from the
patient, without using prior art sponge-weighing methods.
[0058] After the vacuum terminal 42 has been stopped, the hose is
disconnected and the diaphragm 18 is removed from the receptacle 12
by prying open the snap ring 36. The spent or compressed surgical
sponges 16 are removed from the strainer basket 14 for re-use, or
disposal. Typically, the number of surgical sponges 16 in use
during a surgical procedure is known which allows for full
accounting of the surgical sponges 16 prior to closing an incision,
thus ensuring patient safety. The recovered blood 21 in the
receptacle 12 may then be emptied to allow for recovered blood from
a new batch of blood-laden surgical sponges 16. The receptacle 12
may be emptied by a variety of ways, such as, pouring the recovered
blood 21 out into another container or suctioning the recovered
blood 21 via the receptacle opening 26. Accordingly, the receptacle
12 may include a handle depending from the sidewall 24 to
facilitate pouring, and transport of the receptacle 12, or
apparatus 10.
[0059] Alternatively, the apparatus 10 may include a drainage
assembly comprising an outlet in the sidewall 24 and adjacent to
the base 22, with a one-way valve to control egress of the
recovered blood 21 from the reservoir 29 through a tapered spout.
Tubing may be connected to the spout to supply the recovered blood
21 to a blood processing device, such as a cell saver machine or
cardiopulmonary bypass (CPB) machine. A typical cell saver machine
collects, filters, washes and returns the patient's blood to the
patient, such that a closed circulation loop with minimal storage
can be maintained at all times. The cell saver may also measure the
volume of the recovered blood 21. Alternatively, the recovered
blood 21 may be dispensed into another vessel, such as a basin, via
the spout, and the blood is then transferred therefrom to the cell
saver machine or CPB machine.
[0060] Although both the cell-saver machine and the CPB machine
typically include filtering mechanisms for the patient's blood
prior to being reinfused into the patient, a filter may be included
with the perforated body 28 to remove clots, debris, particulates
or foreign material that may be soaked up by the sponges 16.
Therefore, the filter is operable to permit blood to pass
therethrough into the reservoir 29, while acting as a barrier to
the clots, debris, particulates or foreign material. The side wall
24 of the receptacle 12 may include a Heparin coating, or any other
suitable anticoagulant, to delay the clotting of the recovered
blood 21, which may depend on the size of the blood reservoir 29,
the duration the recovered blood 21 is stored in the reservoir 29,
or the frequency of blood 21 removal from the reservoir 29.
[0061] Generally, the apparatus 10 may be fabricated from plastic
materials and is for single-use only in order to enhance patient
safety. Therefore, at the completion of the surgical procedure, all
the components of the apparatus 10 are accounted for, and disposed
of in a similar manner as the other bio-hazard materials.
[0062] In another exemplary embodiment, an exemplary blood recovery
apparatus 60 comprises a receptacle 62 with an opening 64 having a
flange 66 extending outwardly therefrom, as shown in FIG. 4. A lid
68 dimensioned to cover the opening 64 includes a peripheral edge
70 which rests on the flange 66. The lid 68 also comprises an
aperture 72 disposed centrally to locate a bowl 74 which receives
blood-laden sponges 75. The cross-sectional thickness of the lid 68
is dimensioned to permit a passageway to be formed from the
aperture 72 to the peripheral edge 70. Located within the
passageway is a tubing 76 with one end exposed to the opening 64,
and extending beyond the peripheral edge 70, to provide fluid
communication with the aperture 72. The other end of the tubing 76
is connected to a negative pressure source, such as a vacuum
terminal. The tubing 76 may include valve means for controlling
fluid flow therethrough, and a pressure regulator to measure and
control the pressure within the apparatus 60. The bowl 74 comprises
a body with a perforated base 78 dimensioned to fit snugly and
sealingly within the aperture 72. The bowl 74 further comprises an
opening 80 with a flange 82 extending therefrom. A flexible
membrane 84 affixed to an annular snap ring 86 is placed over the
opening 80, such that the snap ring 86 engages the flange 82 to
secure to the flexible membrane 84 to the bowl 74. Accordingly, an
air-tight chamber is defined by the flexible membrane-covered bowl
74 and the receptacle 62. Similar to the diaphragm 18, the flexible
membrane 84 may also include a durable, rigid cover to shield the
flexible membrane 84 from damage due to sharp surgical instruments
or other objects.
[0063] In operation, the bowl 74 is placed within the aperture 72
and blood-laden sponges 75 are introduced into the bowl 74. Next,
the flexible membrane 84 is secured to the bowl opening 80 and then
the external force is applied. Accordingly, as air is drawn from
the air-tight chamber the flexible membrane 84 is caused to
collapse on the blood-laden sponges 75, compressing the blood-laden
sponges 75. The negative pressure and the collapsed flexible
membrane 84 on the blood-laden sponges 75 forces the sponges 75
against the perforated base 78 to urge the blood out. By
maintaining the pressure within a predetermined range, negative
pressure-induced hemolysis of the blood components may be
substantially suppressed. Additionally, any potential hemolytic
effects due to exposure to air are substantially minimized since
the blood is not exposed to air during operation of the apparatus
60. Similar to the receptacle 12, the receptacle 62 may also
include a handle to facilitate transport of the receptacle 62 or
apparatus 60, or pouring the recovered blood into another vessel.
The receptacle 62 may also comprise a drainage assembly comprising
an outlet in the sidewall of receptacle 64, with a one-way valve
for dispensing the blood or connecting to a cell saver machine or
cardiopulmonary bypass (CPB) machine.
[0064] In yet another exemplary embodiment, an exemplary blood
recovery apparatus 90 comprises a receptacle 92 with a base 94, a
sidewall 96, and an opening 98 having a flange 100 extending
outwardly therefrom, as shown in FIG. 5. Located between the base
94 and the opening 98 is a perforated platform 102 on which
blood-laden sponges 104 rest, and a reservoir 106 for the recovered
blood is formed below the perforated platform 102. The sidewall 96
includes one port 108 extending therethrough that connects via a
line to a source of negative pressure, such as a vacuum terminal.
The port 108 or the line is associated with a valve 110 for
controlling fluid flow therethrough, or for preventing reverse
flow, and the valve 110 may include a filter for permitting through
passage of air only. In addition, a pressure regulator within the
receptacle 92 may be included to measure and control the pressure,
thus suppressing or minimizing possible hemolytic effects of the
negative pressure. A float valve 111 within the reservoir 106 may
be included to stop the vacuum terminal, once a float included
therein, and rises with the level of the recovered blood within the
reservoir 106, reaches a predetermined level. A lid 112 dimensioned
to cover the opening 98 includes a peripheral edge 114 which rests
on the flange 100. The lid 112 also includes at least one aperture
116 therethrough in communication with the exterior of the
receptacle 92. Affixed to the peripheral edge 114 is a flexible
membrane 118 in close contact with the blood-laden sponges 104. The
lid 112 is secured to receptacle 92 by forcing the peripheral edge
114 of the lid 112 to the flange 100, such that an air-tight
chamber 120 is defined between the flexible membrane 114 and the
base 94.
[0065] In operation, as air is drawn from the air-tight chamber 120
the flexible membrane 118 is caused to collapse on the blood-laden
sponges 104 and compress the blood-laden sponges 104. The
atmospheric pressure, in combination with the negative pressure and
the collapsing flexible membrane 118 forces the sponges 104 against
the perforated platform 102 to urge the blood out of the sponges
104. The recovered blood is collected in the reservoir 106 and may
be emptied via a drainage assembly 122 connected to another port
124 adjacent to the base 94. Alternatively, the drainage assembly
122 may be connected to a cell saver machine or cardiopulmonary
bypass (CPB) machine. Similar to receptacle 12, the receptacle 92
may also include a handle to facilitate transport of the receptacle
92 or apparatus 90, or pouring the recovered blood into another
vessel.
[0066] In yet another exemplary embodiment, a blood recovery
apparatus 130 comprises a receptacle 132 with a base 134, a
sidewall 136 defining an interior chamber 138, with an opening 140,
as shown in FIGS. 6 to 12. The sidewall 136 also includes ribs 139
depending from the base 134 to the opening 140, and a seat 142 is
formed around the perimeter of the opening 140 and extending away
from the opening 140, and terminating perpendicularly with a ring
wall 144. A spout 146 is formed within a portion of wall 144, and a
port 147 is defined through the sidewall 136 and is connected via a
line to a source of negative pressure, such as a vacuum terminal
(not shown). A valve for controlling fluid flow therethrough, or
for preventing reverse flow, is included, and may include a filter
for allowing air only therethrough. The apparatus 130 also
comprises a strainer basket 148 with a bottom portion 150
dimensioned to be accommodated within the interior chamber 138 and
a top portion 152 with an opening 153, such that the top portion
152 rests on the seat 142. The strainer basket 148 further
comprises a perforated base 154 with a plurality of apertures 156
extending therethrough, with a bottom portion sidewall 158
depending therefrom and terminating at the top portion 152. The
apertures 156 are appropriately dimensioned to enhance drainage of
the recovered blood into the receptacle 132, and may vary in size
and/or shape. A flange 160 is formed with the bottom portion wall
158 and a top portion wall 162, such that the bottom portion wall
158 and the top portion wall 162 are separated by the flange 160
resting on the seat 142. Between the seat 142 and the flange 160 is
a gasket or a seal member 163, such as an 0 ring, which provides an
air-tight seal between the strainer basket 148 and the receptacle
132, during operation.
[0067] Blood-laden sponges 164 are received via the opening 153 and
come to rest on the perforated base 154, and any recovered blood
from the sponges 164 flows via the apertures 156 into a reservoir
157 formed in the interior chamber 138. A lid 165 is introduced via
the opening 153 and exerts pressure on the blood-laden sponges 164
to force the blood out. The lid 165 comprises two disc-shaped
piston heads 166 and 168 dimensioned to engage the top portion wall
162 and the bottom portion wall 158, respectively. The top
disc-shaped piston 166 and the bottom disc-shaped piston 168 are
separated by a plurality of ribs 170. The edge of the disc-shaped
piston 166 includes a seal member 172, such as an 0 ring, or other
suitable seal, which engages the wall 162 of the strainer basket
148. Accordingly, a portion of the seal member 172 is secured
within a recessed channel 175 formed within the edge, while another
portion of the seal member 172 extends outside the channel 175 to
engage the wall 162. Therefore, when the lid 165 is introduced in
the strainer basket 148, the seal member 172 sealingly engages the
top portion wall 162, to form an air-tight chamber between the
piston 166 and the base 134. During operation, as air is drawn out
of the interior chamber 138 by the vacuum terminal, the negative
pressure forces the disc-shaped pistons 166 and 168 towards the
perforated base 154, thus magnifying the force exerted on the
blood-laden sponges 164. The action of the two disc-shaped pistons
166 and 168 moving simultaneously towards the perforated base 154
results in a "double" high-pressure phenomenon on the sponges 164,
which enhances blood recovery therefrom, as shown in FIGS. 9 and
10. For example, with the exemplary two disc-shaped pistons 166 and
168 dimensioned at 6.25 in. and 4.2 in., respectively, when the
pressure source conveys a pressure of 400 mmHg (or 7.735 psi), then
the disc-shaped piston 166 is subject to a force of approximately
237 lb (i.e. 7.735 (6.25/2).sup.2.pi.), and this force translates
to approximately 885 mmHg (i.e. 2374(4.2/2).sup.2.pi.))=17.3 psi)
as the resultant pressure to the disc-shaped piston 168.
Accordingly, the resultant pressure on the sponges 164 is
intensified by this arrangement, with a gain ratio of approximately
2.2. Therefore, the magnitude of the negative pressure conveyed to
the receptacle 132 may be lowered to minimize hemolysis, while
relying more on the intensified pressure conveyed to the
disc-shaped piston 166 to force the blood out of the sponges 164.
Once the blood has been drawn out of the sponges 164 the suction
force is stopped, and the lid 165 is removed from the strainer
basket 148 by pulling on a handle means 176, and the spent sponges
164 are removed from the perforated base 154. Subsequently, the
strainer basket 148 is removed from the receptacle 132 and the
recovered blood is poured out via the spout 146. Advantageously,
since the apparatus 130 comprises only three major parts, that is,
the receptacle 132, the strainer basket 148 and the lid 165, the
apparatus 130 is easily assembled or disassembled to facilitate
emptying of the reservoir 157.
[0068] The recovered blood is collected in the reservoir 157 and
may be emptied via the spout 146. Alternatively, a drainage
assembly is connected to another port adjacent to the base 134 for
emptying the reservoir 157. Further, the drainage assembly may be
connected to a cell saver machine or cardiopulmonary bypass (CPB)
machine.
[0069] In addition, a pressure regulator may be included to measure
and control the pressure within the receptacle 132. While the
handle means 176 aids in the placement of the lid 165 in the
strainer basket 148, and removal of the lid 165 from the strainer
basket 148, it may also be facilitate the application of a force
for manual operation of the apparatus 130.
[0070] Similar to apparatus 10, the apparatus 130 may include a
filter with a perforated body to remove clots, debris, particulates
or foreign material that may be soaked up by the sponges 16.
[0071] In yet another embodiment, positive pressure is applied to
force down the lid 165 of apparatus 130. As such, after the sponges
164 and the lid 165 have been introduced in the strainer basket
148, a cover is placed over the opening 153 to create an air-tight
seal. Positive pressure is introduced via an inlet in the cover.
The positive pressure may be applied by regulated compressed air or
by an air pump. In this embodiment, the outlet 147 to the source of
negative pressure is closed, and thus inoperable. Accordingly, the
system may be adapted for use with a negative pressure source
vacuum source and/or a positive pressure source. Alternatively, a
pressure may be applied manually, for example, the handle 176 of
lid 165 is grasped and a force is exerted to drive the pistons 166
and 168 towards the sponges 164 resting on the perforated base 154.
Electro-mechanical means such as an electric motor coupled to means
for translating rotational motion into longitudinal motion to the
lid 165 may also be employed. As described above, the action of the
two disc-shaped pistons 166 and 168 moving simultaneously towards
the perforated base 154 results in a "double" high-pressure
phenomenon on the sponges 164, which enhances blood recovery
therefrom.
[0072] In yet another exemplary embodiment, an edge of the bottom
disc-shaped piston 168 also includes a seal member, such as an 0
ring, or other suitable seal, secured within a recessed channel 175
formed within the edge, as shown FIGS. 8 to 10. This seal member
engages the wall 162 of the strainer basket 148 and minimizes the
migration of any recovered blood upward or away from the base
134.
[0073] In yet another exemplary embodiment, the blood recovery
apparatus 10 comprises a cylindrical housing with a sidewall
extending from a base to an opening. Located between the base and
the opening is a perforated platform on which blood-laden sponges
rest. A port defined in the sidewall is connected to source of
negative pressure, and a reservoir for the recovered blood is
defined between the base and the port. A disc-shaped piston is
introduced into the housing, and sealingly engages the sidewall to
create an air-tight volume between the piston and the base. As air
is drawn out of the housing, the negative pressure causes the
piston to descend and compress the sponges. Accordingly, the
negative pressure and the force from the piston cause the blood to
drawn from the sponges. The recovered blood may be poured out of
the housing, or alternatively, the housing may include another port
connected to a drainage assembly for emptying the reservoir. The
drainage assembly may be connected to a cell saver machine or
cardiopulmonary bypass (CPB) machine. Similar to the receptacle 12,
the housing may also include a handle to facilitate transport of
the housing, or pouring the recovered blood into another
vessel.
[0074] In yet another exemplary embodiment, the blood recovery
apparatus 10 comprises a flexible housing with a resealable orifice
for introducing blood-laden sponges into the housing and a port
connected to a housing via a hose. The housing is also connected to
a source of negative pressure, such that a partial vacuum is
created in the reservoir. In turn, the partial vacuum causes the
housing to compress the sponges, and causes the blood to be drawn
from the sponges, and flow into the reservoir. The housing interior
may comprise a mesh abutting the sponges, which promotes the flow
of blood out of the housing by maintaining fluid channels.
Alternatively, the housing interior comprises ribs formed to
prevent fluid channels from collapsing as the pressure drops. The
port and/or the hose to the reservoir may include a valve for
regulation of fluid flow, or a pressure intensifier, and a filter
allowing passage of air only. Spent sponges may be removed from the
housing via the orifice, and a fresh batch of blood-laden sponges
may be introduced into the housing. Hemolytic effects due to
pressure and air may be substantially minimized using previously
discussed techniques.
[0075] Although in the foregoing embodiments the method and system
for recovering blood have been described as being useful in an
intra-operative setting, the method and system are also operable or
potentially viable in a post-operative care setting, such as a
recovery unit or care unit, including other applications.
[0076] In any of the above embodiments, in order to delay the
clotting of the recovered blood, a Heparin coating, or any other
suitable anticoagulant, may be added to the interior walls of the
reservoir in contact with blood.
[0077] In another embodiment, any of the exemplary apparatus
described above may be used in other commercial applications, such
as forcing fluid or liquid from any absorbent material. For
example, in one application oil is forced out of oil-soaked sponges
or rags in environmental clean-up procedures. Another application
may be in the janitorial cleaning services or household cleaning,
for wringing liquid-absorbent materials or devices, such as mops,
sponges or rags. As those of skill will appreciate, the
afore-mentioned apparatuses may be modified to suit the desired
application.
[0078] Benefits, other advantages, and solutions to problems have
been described above with regard to specific embodiments. However,
the benefits, advantages, solutions to problems, and any element(s)
that may cause any benefit, advantage, or solution to occur or
become more pronounced are not to be construed as critical,
required, or essential features or elements of any or all the
claims. As used herein, the terms "comprises," "comprising," or any
other variations thereof, are intended to cover a non-exclusive
inclusion, such that a process, method, article, or apparatus that
comprises a list of elements does not include only those elements
but may include other elements not expressly listed or inherent to
such process, method, article, or apparatus. Further, no element
described herein is required for the practice of the invention
unless expressly described as "essential" or "critical."
[0079] The preceding detailed description of exemplary embodiments
of the invention makes reference to the accompanying drawings,
which show the exemplary embodiment by way of illustration. While
these exemplary embodiments are described in sufficient detail to
enable those skilled in the art to practice the invention, it
should be understood that other embodiments may be realized and
that logical and mechanical changes may be made without departing
from the spirit and scope of the invention. For example, the steps
recited in any of the method or process claims may be executed in
any order and are not limited to the order presented. Further, the
present invention may be practiced using one or more servers, as
necessary. Thus, the preceding detailed description is presented
for purposes of illustration only and not of limitation, and the
scope of the invention is defined by the preceding description, and
with respect to the attached claims.
* * * * *